Chapter 8: covalent bonding Flashcards
Why do covalent bonds form
when atoms get close the electrons see eachother’s nuecleus with a powerful positive charge.
In covalent bonds_____ are ______
valence; shared
Bonds forming____ energy
releases
Bonds breaking_____ energy
takes energy
Sigma Bond
look down neucleous axis and turn it cylindrically= symetrical end to end s and p p and p s and s sing bonds
Pi Bonds
Side to side overlab
no s(because a sphere doesn’t have a side)
remaining bonds in multiple bonds bonds.
Enthalpy
the strength of a bond measured by how much energy is required to break it
Averge bond enthalpies are_____
positive because bond breaking is an endothermic process
Bond length is measured in___
Angstrums
What makes a bond strong
the shorter a bond is the stronger it is.
As the bonds increase in number it becomes shorter.
Nomenclature of Binary molecular compounds
- name the least electronegative atom. Use prefixes other than mono.
- name most electronegative and add ide
- if the prefix ends with an o or an a and the name of the element begins with a vowel, the two vowels mesh.
Naming acids(H)
- if the anion in the acid ends in ide, change the ending to ic acid and add the prefix hydro
- if the anion ends in ate change the end to ic acid and do not add hydro
- if the anion ends in ite change the ending to ous acid.
Polar covalent
small diference of electronegativity
a bond with electronegativity difference greater than 1.7
Ionic
electronegativity difference from .4 to 1.7
polar covalent
